Laboratory work 1 Calculation of the recipe, preparation, and analysis of natural food coloring (caramel color) E150a

DETERMINATION OF EXTRACTIVE SUBSTANCES
Materials and equipment: refractometer RPL-3 or IRF-454M, color, distilled water, filter paper, glass stick.
Determination technique. A few drops of color are placed between the lighting and measuring prisms of the refractometer, while the wand should not touch the prisms. Take readings, if necessary, take into account the correction for temperature. Immediately after the determination, the surface of the prisms is wiped with filter paper, and then washed with distilled water.
COLOR DETECTION
Materials and equipment: laboratory scales, glass beaker, graduated pipette, kohler, iodine solution of a molar concentration equivalent to 0.1 mol/ , distilled water.
Determination technique. The color of 100 , of a 1% kohler solution is assumed to be equivalent to the color of an iodine solution of a molar concentration equivalent to 0.1 mol/ ,.
A sample of color (about 1 g) is dissolved in 99 , of distilled water; 50 cm3 of the resulting solution is introduced into a cylinder or a colorimetric glass; 47-48 , of distilled water is poured into another cylinder or a colorimetric glass, added drop by drop using a graduated pipette with a capacity of 1 , with constant stirring, the iodine solution is leveled until the color in both vessels. The color of the color is determined by the formula
C = 2 А,
where C is the color of the color, cm3 0.1 mol / , of the I2 solution;
A is the volume of the molar concentration equivalent of 0.1 mol / , , spent on titration of the iodine solution.
Entry in the workbook: the volume spent on titration of the iodine solution of a molar concentration equivalent of 0.1 mol / , (A), ,
color of the color (C), ,
0.1 mol / , of the solution; mass fraction of extractive substances of the color, %; conclusion.
Control question:
1. What are the main methods of obtaining and application of caramel color (E 150)?
2. What reaction underlies the formation of a sugar buffer?
3. What products are formed as a result of caramelization of sugars?
4. What is used to reduce the foaming of the color during its preparation?
5. How is the color of the sugar color estimated?